1. Field of the Invention
This invention relates to method and apparatus for assembling aircraft components particularly for positioning such components with a jig assembly for fastening same.
2. The Prior Art
Assembling and fastening together elements of aircraft components is a multi-step process. For example, elements of a wing spar assembly includes, eg. an aluminum web, two angle caps and several stiffeners. Once these elements or details are located, a problem lies in the high man-hour requirements needed to prepare and position the elements for assembly in an automatic fastening operation as found in modern aircraft assembly plants. Such preparation process would normally require the manual drilling and installation of many (eg. 500) temporary fasteners (tacking) to hold the spar assembly in position, as guided by a jig for that purpose. After the tacking process, the spar assembly is then removed from the assembly jig and transferred to a fastening stage to be fastened eg. by rivets.
In the prior art, several patents relate to aircraft structures and methods of assembly including U.S. Pat. No. 3,827,661 to Ryan et al. (1974), U.S. Pat. No. 3,643,900 to Malony (1972), U.S. Pat. No. 2,567,124 to Roberts (1951) and U.S. Pat. No. 2,430,438 to Watter et al (1943). Although these patents relate to the assembly of airfoils and at least one, the Ryan reference, mentions the use of quick release fasteners to hold the assembly in alignment before riveting same, but appears to take no notice of the tacking problem, let alone suggest a solution therefor.
The above-mentioned assembly and positioning of spar elements in a jig, normally requires a considerable number of man hours for installing what are only temporary fasteners, ie. tacking, as noted above.
Accordingly, there is a need and market for a jig assembly method and apparatus that omits or eliminates tacking in the assembly of aircraft components and otherwise obviates the above prior art shortcomings.
There has now been discovered method and apparatus for jig assembly and positioning of aircraft components that employs a "no tack" concept that significantly reduces the man hour costs in jig assembly preparation for subsequent permanent fastening of aircraft elements and/or components.